public class Ocean {
 public static void main(String[] args) {
   doSwim(new Anemonefish("尼莫"));
   doSwim(new Shark("兰尼"));
   doSwim(new Human("贾斯汀"));
   doSwim(new Submarine("黄色一号"));
   doSwim(new Piranha("比克"));
 }

 static void doSwim(Swimmer swimmer) {
   swimmer.swim();
 }
}

